PURPOSE: To improve the flexibility in the attaching conditions, in a simultaneous air intake and exhausting type ventilating device including a centrifugal type multiple blade fan and arc shaped air intake and exhausting housing, by forming a communicating path to the outdoors by a soft synthetic resin pipe having a bellows shape.

CONSTITUTION: A convex part 82 of an exhausting sleeve 81 is engaged with a concave part 84 provided in the flange of an exhausting pipe 28 which is protruded to the outside from a back cover 5 of the ventilating device, and the outdoor air exhausting part is formed. A flexible pipe formed in the bellows shape 85 by the soft synthetic resin is used for the exhausting sleeve 81. In this constitution, the device is not subjected to the effects such as collapse of a wall hole and the shape of a weather cover, and the attaching flexibility can be improved.